The aim of this study was to evaluate the effectiveness of root canal preparation with Nitiflex file and Flexofile. Forty mesio-buccal upper molar roots were used. After the preparation, the root canals were molded using an impression paste being then examined for the presence or absence of apical deviation, taper and surface. The results did not indicate any statistical difference between the use of the two types of instruments.
Endodontics; Root canal therapy; Dental instruments
